Prevent deadlock when removing routes w/o engine

diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index ae354646b97885b414437c4a34ee621ff107efd5..f5920f96e48decabcb84f615ab50ea26b13ab582 100644 (file)
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -3814,7 +3814,7 @@ Session::remove_routes (boost::shared_ptr<RouteList> routes_to_remove)
                resort_routes ();
 #endif
 
-       if (_process_graph && !(_state_of_the_state & Deletion)) {
+       if (_process_graph && !(_state_of_the_state & Deletion) && _engine.running()) {
                _process_graph->clear_other_chain ();
        }